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Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
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Showing 81 to 88 of 88 (0.027 seconds)Spelling suggestions: "subject:"roadnetwork"" "subject:"cradtnetwork""
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Derivation of continuous zoomable road network maps through utilization of Space-Scale-CubeAliakbarian, Meysam January 2013 (has links)
The process of performing cartographic generalization in an automatic way applied on geographic information is of highly interest in the field of cartography, both in academia and industry. Many research e↵orts have been done to implement di↵erent automatic generalization approaches. Being able to answer the research question on automatic generalization, another interesting question opens up: ”Is it possible to retrieve and visualize geographic information in any arbitrary scale?” This is the question in the field of vario-scale geoinformation. Potential research works should answer this question with solutions which provide valid and efficient representation of geoinformation in any on-demand scale. More brilliant solutions will also provide smooth transitions between these on-demand arbitrary scales. Space-Scale-Cube (Meijers and Van Oosterom 2011) is a reactive tree (Van Oosterom 1991) data structure which shows positive potential for achieving smooth automatic vario-scale generalization of area features. The topic of this research work is investigation of adaptation of this approach on an interesting class of geographic information: road networks datasets. Firstly theoretical background will be introduced and discussed and afterwards, implementing the adaptation would be described. This research work includes development of a hierarchical data structure based on road network datasets and the potential use of this data structure in vario-scale geoinformation retrieval and visualization.:Declaration of Authorship i
Abstract iii
Acknowledgements iv
List of Figures vii
Abbreviations viii
1 Introduction 1
1.1 Problem Definition 2
1.1.1 Research Questions 2
1.1.2 Objectives 3
1.2 Proposed Solution 3
1.3 Structure of the Thesis 4
1.4 Notes on Terminology 4
2 Cartographic Generalization 6
2.1 Cartographic Generalization:
Definitions and Classifications 6
2.2 Generalization Operators 9
2.3 Efforts on Vario-Scale Visualization of Geoinformation 10
2.4 Efforts on Generalization of Road Networks and Similar Other Networks 16
2.4.1 Geometric Generalization of Networks 17
2.4.2 Model Generalization of Networks 18
2.5 Clarification of Interest 20
3 Theory of Road Network SSC 21
3.1 Background of an SSC 21
3.1.1 tGAP 21
3.1.2 Smoothing tGAP 23
3.2 Road Network as a ’Network’ 24
3.2.1 Short Background on Graph Theory 5
3.3 Formation of Road Network SSC 26
3.3.1 Geometry 26
3.3.2 Network Topology 27
3.3.3 Building up tGAP on The Road Network 28
3.3.4 Smoothing of Road Network SSC 31
3.3.4.1 Smoothing Elimination 32
3.3.4.2 Smoothing Simplification 32
3.4 Reading from a road network SSC 34
3.4.1 Discussion on Scale 34
3.4.2 Iterating Over The Forest 35
3.4.3 Planar Slices 35
3.4.4 Non-Planar Slices 36
4 Implementation of Road Network SSC 37
4.1 General Information Regarding The Implementation 37
4.1.1 Programming Language 37
4.1.2 RDBMS 38
4.1.3 Geometry Library 39
4.1.4 Graph Library 39
4.2 Data Structure 40
4.2.1 Node 40
4.2.2 Edge 41
4.2.3 Edge-Node-Relation 41
4.3 Software Architecture 42
4.3.1 More Detail on Building The SSC 42
4.3.1.1 Initial Data Processing 42
4.3.1.2 Network Processing 43
4.3.2 More Detail on Querying The SSC 46
4.3.2.1 Database Query 46
4.3.2.2 Building Geometry 46
4.3.2.3 Interface and Visualization 47
4.4 Results 48
5 Conclusions and Outlook 49
Bibliography 51
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Résolution d’un problème de collecte et livraison dynamique sur un réseau routier avec temps de parcours variablesCaron, Félix 03 1900 (has links)
Les services de livraison express font face au défi d’optimiser les routes de leurs véhicules alors que ceux-ci circulent dans un réseau routier où les temps de parcours varient en fonction du moment de la journée et où ils doivent répondre à l’arrivée dynamique de requêtes consistant à récupérer et livrer des colis. Notre but ici est de proposer une modélisation et une méthode de type heuristique pour résoudre ce problème. Nous commençons par explorer les travaux menés précédemment au sujet de l’arrivée dynamique des requêtes, des temps de parcours variables selon le moment de la journée et des collectes et livraisons dans les problèmes de tournées de véhicules. Ensuite, nous décrivons le problème de manière formelle sur le graphe du réseau routier avec des requêtes deux-points où l’objectif est de minimiser le temps total de parcours des véhicules et les temps de retard aux points de service et au dépôt. Par la suite, nous détaillons l’implémentation d’une méthode de résolution basée sur la recherche tabou utilisant une structure de voisinage basée sur la réinsertion d’une requête. Cette méthode utilise également la structure Dominant Shortest Path (DSP) qui considère plusieurs chemins alternatifs entre chaque paire de sommets, contrairement à l’approche traditionnelle où un chemin unique est fixé a priori. Finalement, nous testons notre méthode à l’aide de 390 instances générées de manière synthétique afin d’évaluer son efficacité ainsi que l’impact de certains aspects du problème et de la méthode de résolution. Les résultats démontrent une amélioration particulièrement importante due à l’utilisation de la structure DSP. / Express delivery services face the challenge of optimizing the routes of their vehicles while they are moving in a road network where the travel times vary according to the time of day in order to serve dynamic requests which consist in collecting and delivering parcels. Our goal here is to propose a model and a heuristic method to solve this problem. We begin by exploring previous work on the topic of the dynamic arrival of requests, timedependent travel times and pickups and deliveries in vehicle routing problems. Afterwards, we describe the problem formally on the graph of the road network with the objective of minimizing the total travel time of the vehicles and lateness at the service points and at the depot. Then, we detail the implementation of a solving method based on tabu search using a neighbourhood structure based on the reinsertion of a request. This method also uses the Dominant Shortest Path (DSP) structure which considers multiple alternative paths between each pair of vertices, unlike the traditional approach where a single path is fixed a priori. Finally, we test our method using 390 instances generated synthetically in order to evaluate its efficiency as well as the impact of certain aspects of the problem and solution method. The results show a particularly significant improvement due to the use of the DSP structure.
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Modelle zur Beschreibung der Verkehrssicherheit innerörtlicher Hauptverkehrsstraßennetze unter besonderer Berücksichtigung der Umfeldnutzung / Accident prediction models for urban main road networks considering the adjacent land-useAurich, Allan 15 November 2013 (has links) (PDF)
In der Arbeit wird eine Methodik einer zusammenhängenden Analyse und modellhaften Beschreibung der Verkehrssicherheit in städtischen Hauptstraßennetzen am Beispiel der Stadt Dresden entwickelt. Die dabei gewonnenen Modelle dienen der Abschätzung von Erwartungswerten von Unfallhäufigkeiten mit und ohne Personenschaden unter Berücksichtigung der Verkehrsbeteiligungsart.
Die Grundlage bilden multivariate Regressionsmodelle auf Basis verallgemeinerter linearer Modelle (GLM). Die Verwendung verallgemeinerter Regressionsmodelle erlaubt eine Berücksichtigung von Verteilungen, die besser geeignet sind, den Unfallentstehungsprozess wiederzugeben, als die häufig verwendete Normalverteilung. Im konkreten Fall werden hierzu die Poisson-Verteilung sowie die negative Binomialverteilung verwendet.
Um Effekte im Hauptverkehrsstraßennetz möglichst trennscharf abbilden zu können, werden vier grundsätzliche Netzelemente differenziert und das Netz entsprechend zerlegt. Unterschieden werden neben Streckenabschnitten und Hauptverkehrsknotenpunkten auch Annäherungsbereiche und Anschlussknotenpunkte. Die Kollektive der Knotenpunkte werden ferner in signalisierte und nicht-signalisierte unterteilt. Es werden zunächst Modelle unterschiedlicher Unfallkollektive getrennt für alle Kollektive der vier Netzelemente berechnet. Anschließend werden verschiedene Vorgehensweisen für eine Zusammenfassung zu Netzmodellen entwickelt.
Neben der Verwendung verkehrstechnischer und infrastruktureller Größen als erklärende Variable werden in der Arbeit auch Kenngrößen zur Beschreibung der Umfeldnutzung ermittelt und im Rahmen der Regression einbezogen. Die Quantifizierung der Umfeldnutzung erfolgt mit Hilfe von Korrelations-, Kontingenz- und von Hauptkomponentenanalysen (PCA).
Im Ergebnis werden Modelle präsentiert, die eine multivariate Quantifizierung erwarteter Unfallhäufigkeiten in Hauptverkehrsstraßennetzen erlauben. Die vorgestellte Methodik bildet eine mögliche Grundlage für eine differenzierte Sicherheitsbewertung verkehrsplanerischer Variantenabschätzungen. / A methodology is developed in order to predict the number of accidents within an urban main road network. The analysis was carried out by surveying the road network of Dresden. The resulting models allow the calculation of individual expectancy values for accidents with and without injury involving different traffic modes.
The statistical modelling process is based on generalized linear models (GLM). These were chosen due to their ability to take into account certain non-normal distributions. In the specific case of accident counts, both the Poisson distribution and the negative binomial distribution are more suitable for reproducing the origination process than the normal distribution. Thus they were chosen as underlying distributions for the subsequent regressions.
In order to differentiate overlaying influences, the main road network is separated into four basic elements: major intersections, road sections, minor intersections and approaches. Furthermore the major and minor intersections are additionally subdivided into signalised and non-signalised intersections. Separate models are calculated for different accident collectives for the various types of elements. Afterwards several methodologies for calculating aggregated network models are developed and analysed.
Apart from traffic-related and infrastructural attributes, environmental parameters are derived taking into account the adjacent building structure as well as the surrounding land-use, and incorporated as explanatory variables within the regression. The environmental variables are derived from statistical analyses including correlation matrices, contingency tables and principal components analyses (PCA).
As a result, a set of models is introduced which allows a multivariate calculation of expected accident counts for urban main road networks. The methodology developed can serve as a basis for a differentiated safety assessment of varying scenarios within a traffic planning process.
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Modeling of complex network, application to road and cultural networks / Modeling of complex network, application to road and cultural networksJiang, Jian 12 September 2011 (has links)
De nombreux systèmes complexes provenant de phénomènes naturels ou de la société humaine peuvent être décrits comme des réseaux complexes. Dans cette thèse, sur la base de la théorie des réseaux complexes, nous allons nous pencher sur la structure topologique de ces réseaux complexes et leurs dynamiques. Nous avons créé des modèles pour étudier les influences de la structure sur la dynamique des réseaux et mis en évidence quelques propriétés particulières des systèmes complexes. Cette thèse comporte quatre parties. Dans la première partie, les propriétés empiriques (degré de distribution, coefficient d’agrégation, diamètre, longueur caractéristique de parcours) des réseaux de routes urbaines de la ville du Mans en France sont étudiées. Dans la seconde partie, nous proposons deux modèles pour étudier le mécanisme éventuel conduisant à s’écarter de la loi de puissance simple. Dans le premier modèle, la probabilité d’addition de noeuds et de liens, la création de liens est étudiée ; dans le second modèle, seule la croissance aléatoire et préférentielle de liens est ajoutée. Les résultats de la simulation de ce modèle sont comparés aux données réelles. Dans la troisième partie, les propriétés probabilistes incertaines de la loi de distribution en double puissance sont étudiées. L’optimisation du réseau et l’étude optimale du réseau sans échelle vers l’échec aléatoire sont étudiées en se servant du principe de maximisation de l’entropie. Nous avons défini l’ensemble du réseau à l’équilibre comme des ensembles stationnaires de graphes en utilisant des notions thermodynamiques telle que ”énergie”, ”température”, ” énergie libre” pour les réseaux. Dans la quatrième partie, un modèle d’union-division est mis au point pour étudier l’évolution temporelle de certains réseaux culturels ou économiques. Dans ce modèle, les noeuds représentent les cultures. Plusieurs grandeurs telles que la richesse, l’âge, identité, contenu etc. sont utilisées pour paramétrer l’évolution probable du réseau. Le modèle offre une vision à long terme sur une dynamique apparemment périodique d’ensemble de grandeurs culturelles ou économiques en interaction. / Many complex systems arising from nature and human society can be described as complex networks. In this dissertation, on the basis of complex network theory, we pay attention to the topological structure of complex network and the dynamics on it. We established models to investigate the influences of the structure on the dynamics of networks and to shed light on some peculiar properties of complex systems. This dissertation includes four parts. In the first part, the empirical properties (degree distribution, clustering coefficient, diameter, and characteristic path length) of urban road network of Le Mans city in France are studied. The degree distribution shows a double power-law which we studied in detail. In the second part, we propose two models to investigate the possible mechanisms leading to the deviation from simple power law. In the first model, probabilistic addition of nodes and links, and rewiring of links are considered; in the second one, only random and preferential link growth is included. The simulation results of the modelling are compared with the real data. In the third part,the probabilistic uncertainty behavior of double power law distribution is investigated. The network optimization and optimal design of scale free network to random failures are discussed from the viewpoint of entropy maximization. We defined equilibrium network ensemble as stationary ensembles of graphs by using some thermodynamics like notions such as ”energy”, ”temperature”, ”free energy” for network. In the forth part, an union-division model is established to investigate the time evolution of certain networks like cultural or economical networks. In this model, the nodes represent, for example, the cultures. Several quantities such as richness, age, identity, ingredient etc. are used to parameterize the probabilistic evolution of the network. The model offers a long term view on the apparently periodic dynamics of an ensemble of cultural or economic entities in interaction.
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Simulace provozu na silnicích a dálnicích / Simulation of Traffic on Roads and HighwaysZajdák, Jiří January 2011 (has links)
This thesis deals with a simulation of traffic on roads and highways. The thesis analyzes important concepts of road traffic law and their relation to simulation system. Further are here described problems of design and creation of traffic network which simulator uses. Work explains principles of models of behaviour of traffic participants which are extensible by force of plug-ins. The thesis also valorizes how many details is advisable to model the reality in particular parts of simulating system.
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Modelle zur Beschreibung der Verkehrssicherheit innerörtlicher Hauptverkehrsstraßennetze unter besonderer Berücksichtigung der UmfeldnutzungAurich, Allan 17 May 2013 (has links)
In der Arbeit wird eine Methodik einer zusammenhängenden Analyse und modellhaften Beschreibung der Verkehrssicherheit in städtischen Hauptstraßennetzen am Beispiel der Stadt Dresden entwickelt. Die dabei gewonnenen Modelle dienen der Abschätzung von Erwartungswerten von Unfallhäufigkeiten mit und ohne Personenschaden unter Berücksichtigung der Verkehrsbeteiligungsart.
Die Grundlage bilden multivariate Regressionsmodelle auf Basis verallgemeinerter linearer Modelle (GLM). Die Verwendung verallgemeinerter Regressionsmodelle erlaubt eine Berücksichtigung von Verteilungen, die besser geeignet sind, den Unfallentstehungsprozess wiederzugeben, als die häufig verwendete Normalverteilung. Im konkreten Fall werden hierzu die Poisson-Verteilung sowie die negative Binomialverteilung verwendet.
Um Effekte im Hauptverkehrsstraßennetz möglichst trennscharf abbilden zu können, werden vier grundsätzliche Netzelemente differenziert und das Netz entsprechend zerlegt. Unterschieden werden neben Streckenabschnitten und Hauptverkehrsknotenpunkten auch Annäherungsbereiche und Anschlussknotenpunkte. Die Kollektive der Knotenpunkte werden ferner in signalisierte und nicht-signalisierte unterteilt. Es werden zunächst Modelle unterschiedlicher Unfallkollektive getrennt für alle Kollektive der vier Netzelemente berechnet. Anschließend werden verschiedene Vorgehensweisen für eine Zusammenfassung zu Netzmodellen entwickelt.
Neben der Verwendung verkehrstechnischer und infrastruktureller Größen als erklärende Variable werden in der Arbeit auch Kenngrößen zur Beschreibung der Umfeldnutzung ermittelt und im Rahmen der Regression einbezogen. Die Quantifizierung der Umfeldnutzung erfolgt mit Hilfe von Korrelations-, Kontingenz- und von Hauptkomponentenanalysen (PCA).
Im Ergebnis werden Modelle präsentiert, die eine multivariate Quantifizierung erwarteter Unfallhäufigkeiten in Hauptverkehrsstraßennetzen erlauben. Die vorgestellte Methodik bildet eine mögliche Grundlage für eine differenzierte Sicherheitsbewertung verkehrsplanerischer Variantenabschätzungen. / A methodology is developed in order to predict the number of accidents within an urban main road network. The analysis was carried out by surveying the road network of Dresden. The resulting models allow the calculation of individual expectancy values for accidents with and without injury involving different traffic modes.
The statistical modelling process is based on generalized linear models (GLM). These were chosen due to their ability to take into account certain non-normal distributions. In the specific case of accident counts, both the Poisson distribution and the negative binomial distribution are more suitable for reproducing the origination process than the normal distribution. Thus they were chosen as underlying distributions for the subsequent regressions.
In order to differentiate overlaying influences, the main road network is separated into four basic elements: major intersections, road sections, minor intersections and approaches. Furthermore the major and minor intersections are additionally subdivided into signalised and non-signalised intersections. Separate models are calculated for different accident collectives for the various types of elements. Afterwards several methodologies for calculating aggregated network models are developed and analysed.
Apart from traffic-related and infrastructural attributes, environmental parameters are derived taking into account the adjacent building structure as well as the surrounding land-use, and incorporated as explanatory variables within the regression. The environmental variables are derived from statistical analyses including correlation matrices, contingency tables and principal components analyses (PCA).
As a result, a set of models is introduced which allows a multivariate calculation of expected accident counts for urban main road networks. The methodology developed can serve as a basis for a differentiated safety assessment of varying scenarios within a traffic planning process.
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Исследование и оптимизация городских автобусных перевозок на примере пассажирского автотранспортного предприятия АП-3 г. Екатеринбурга : магистерская диссертация / Research and optimization of urban bus transport on the example of passenger transport enterprise AP-3 YekaterinburgПазылидинов, И. А., Pazylidinov, I. A. January 2018 (has links)
In this work, the current state and prospects of development of urban passenger transport in the operating conditions of the city of Yekaterinburg of the Sverdlovsk region are investigated and analyzed.
The analysis and evaluation of the management and organization of passenger traffic to urban passenger transport in the city of Yekaterinburg.
The solution of the problem of dispatching control and organization of passenger traffic in the urban cycle by mathematical modeling and optimization is considered.
A General view of the simulation model of the automated system of urban passenger transport management by levels is developed. It also proposes the structure of management and organization of urban passenger transport. / В данной работе исследована и проанализирована современное состояние и перспективы развитие городского пассажирского транспорта в условиях эксплуатации города Екатеринбург Свердловской области.
Изложена анализ и оценка эффективности управления и организации пассажиропотока городским пассажирским транспортам в городе Екатеринбург.
Рассмотрена решение проблемы диспетчеризации управления и организации пассажирских перевозок в городском цикле математическим методом моделирования и оптимизации.
Разработан общий вид имитационной модели автоматизированной системы управлении городского пассажирского транспорта по уровням. А также предлагается структура управления и организации городского пассажирского транспорта.
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GIS-based Episode Reconstruction Using GPS Data for Activity Analysis and Route Choice Modeling / GIS-based Episode Reconstruction Using GPS DataDalumpines, Ron 26 September 2014 (has links)
Most transportation problems arise from individual travel decisions. In response, transportation researchers had been studying individual travel behavior – a growing trend that requires activity data at individual level. Global positioning systems (GPS) and geographical information systems (GIS) have been used to capture and process individual activity data, from determining activity locations to mapping routes to these locations. Potential applications of GPS data seem limitless but our tools and methods to make these data usable lags behind. In response to this need, this dissertation presents a GIS-based toolkit to automatically extract activity episodes from GPS data and derive information related to these episodes from additional data (e.g., road network, land use).
The major emphasis of this dissertation is the development of a toolkit for extracting information associated with movements of individuals from GPS data. To be effective, the toolkit has been developed around three design principles: transferability, modularity, and scalability. Two substantive chapters focus on selected components of the toolkit (map-matching, mode detection); another for the entire toolkit. Final substantive chapter demonstrates the toolkit’s potential by comparing route choice models of work and shop trips using inputs generated by the toolkit.
There are several tools and methods that capitalize on GPS data, developed within different problem domains. This dissertation contributes to that repository of tools and methods by presenting a suite of tools that can extract all possible information that can be derived from GPS data. Unlike existing tools cited in the transportation literature, the toolkit has been designed to be complete (covers preprocessing up to extracting route attributes), and can work with GPS data alone or in combination with additional data. Moreover, this dissertation contributes to our understanding of route choice decisions for work and shop trips by looking into the combined effects of route attributes and individual characteristics. / Dissertation / Doctor of Philosophy (PhD)
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